The single most important thing you need to know about eating with type 1 diabetes

Having type 1 diabetes does not mean that you can or cannot eat certain foods!

However, what is important to know is when is best to eat different foods to assist your diabetes management and to keep your blood glucose levels within your target range.

Before you plan your nutritional intake it is important to know what different nutrients are used for in the body. This may seem confusing to start with so it is important to give some background to different what different nutrients do.


These are the major energy source for the body. Carbohydrates are broken down in the body into glucose and absorbed into the bloodstream where it is used for energy. This therefore causes blood glucose levels to rise in people with diabetes. They are also used to power the body’s involuntary functions, such as the heartbeat, breathing and digestive processes.

Carbohydrates come in two main forms; simple and complex. (Warning! A little science here..) Complex carbohydrates have longer chains of sugar molecules and therefore take longer for the body to break down than simple carbohydrates. This generally makes complex carbohydrates a much more sensible dietary choice (the caveat here is that some healthful foods contain simple carbohydrates and complex carbohydrates can sometimes be found in food with low nutritional value. Simple carbohydrates are also useful if you have hypoglycaemia).

Complex carbohydrates = slow release

Simple carbohydrates = fast release

Foods that contain carbohydrates: grains, bread, rice, pasta, vegetables, fruits, sugars, dairy products.

Complex carbohydrates examples: brown rice, wholemeal bread, barley, oats, vegetables, nuts.

Simple carbohydrates examples: sugar, sweets, sugary drinks, fruit juice, products with added sugar.

Top Tip

Try to avoid sugary drinks and fruit juice as a way of quenching thirst. These can be replaced with water, diet soft drinks and tea/coffee. If you want to know more about tea and coffee consumption and diabetes you can find our article here.


Proteins are used to build and repair tissues and is an important building block of bones, muscles, cartilage, skin, and blood. It is rare that people in developed countries such as the UK do not get enough protein in their diets. However, if you are vegetarian or vegan it is important to include a variety of protein-rich plant foods such as beans, nuts and whole grains to ensure and optimal combination on amino acids are consumed.

Foods that contain protein: seafood, meat, eggs, beans, milk, cheese, yogurt, nuts, seeds, tofu, chickpeas.

Lipids (Fat)

There are four different types of fat. Some types are classed as healthy whilst others the complete opposite (confusing we know). Different fats are known as monounsaturated, polyunsaturated, saturated, and trans fats. The latter two of which are branded unhealthy.

You may notice difficulties managing blood sugar after eating a meal high in saturated or trans fats, for example after a takeaway, where your blood sugar will rise a number of hours after consumption.

This is because fats delay the rate at which the stomach empties, which actually slows down the absorption of glucose. This sounds great for diabetics, however high fat foods (particularly saturated and trans fats) can be very harmful to the body.

Wherever possible it is recommended to replace saturated and trans fats with small amounts of monounsaturated and polyunsaturated fats.

Monounsaturated fat: avocados, olives, olive oil, almonds, cashews, hazelnuts, peanuts, pistachios.

Polyunsaturated fat: oily fish, flaxseed, pine nuts, sesame seeds, sunflower seeds, walnuts.

Saturated fat: processed meat (e.g. sausages, ham, burgers), whole milk, cheese, butter, cream.

Trans fat: fried food, takeaways, biscuits, cakes, pastries.

Vitamins and Minerals

These are the two main types of nutrients that your body needs to survive and stay healthy.

Vitamins help you to resist infections, keep your nerves healthy and make sure your blood clots properly.

Minerals also help your body to function in a number of ways. Minerals are used to build strong bones, transmit nerve impulses and even maintain a normal heartbeat.

The majority of vitamins and minerals will be consumed through a healthy and balanced diet.


Counting Carbohydrates

It is good to include some carbohydrates to prevent your blood sugar going too low – it is also a fuel for the body. However, low carb diets may be beneficial if you are struggling to keep control of your blood glucose levels.

Counting carbs helps you keep track of how many carbs you eat. You can work with your doctor or a dietitian to figure out how many grams of carbs you should eat for each meal and snack and amount of insulin you should allocate for this.


Glycaemic Index

Glycaemic index (GI) is another important factor when assessing nutritional intake. It is a number from 0 to 100 that tells us the rate at which a food raises blood glucose levels. This makes it extremely useful for people with diabetes to understand GI ratings for different foods. We have written an article on the glycaemic index here.


Don’t feel overwhelmed by all of this information, it will all start to make sense with a little persistence. The most important things to consider are when eating are:

Starting glucose level: this may impact the amount of insulin allocated, e.g. if you are a little high to start with you may need to allocate a little more insulin for a correction

Amount of carbohydrates in food (and, are these complex or simple?): this will heavily dictate amount of insulin allocated, ideally based on your carb counting ratio.

Amount of fat in food and GI rating: these will impact the rate at which the carbohydrate is absorbed in the body. High GI food may be great if blood glucose is low for example.

Physical activity: how active have you been today or are you planning to be in the next couple of hours? E.g. if you have been active you may need to lower doses as the body will be using more carbohydrates as energy.

If you consider these 4 key areas when planning your food intake and diabetes management then it should make it easier to plan insulin dosages and hopefully keep a tighter control of blood glucose levels.

As always, please consult health professionals before changing your management process. This post is for educational purposes only.


Leave a comment

Please note, comments must be approved before they are published